Roll forming of sheet material



J1me 1965 R. H. SHULTZ ETAL 3,187,539

ROLL FORMING OF SHEET MATERIAL Filed May 17. 1960 2 Sheets-Sheet 1RIC/MRO H SHUL rz Rum. 7. SCHENCK mmvroxs ATTORNEYS June 8, 1965 R. H.SHULTZ ETAL 3,187,539

ROLL FORMING OF SHEET MATERIAL Filed May 17, 1960 2 Sheets-Sheet 2RICHARD H Sam 72 s, Rum. 7. 5CHENCK 30 INVENTORS ATTORNEYS ROLL FORMINGOF SHEET MATERIAL Richard H. Shultz, La Grange, and Ruhl T. Schenck,

Chicago, Ill.,.assignors to Continental Can Company, Inc., New York,N.Y., a corporation of New York Filed May 17, 1960, Ser. No. 29,671 8Claims. (Cl. 72-180) This invention relates in general to new and usefulimprovements in the art of forming cylindrical members of sheetmaterial, and more particularly relates to a novel method of rollforming sheet material in the forming of can bodies.

In the operation of a conventional can body maker, the sheet metal blankis moved'longitudinally until it is in transverse alignment with a setof roll-s, at which time it must be stopped. The direction of movementof the body blank is then changed 90 degrees to put it through the setof rolls, after which it is again stopped. The curved blank then has itsdirection of movement again changed 90 degrees so that it may continuein its original direction through the remainder of the canwbody maker.It is, of course, apparent that it i undesirable to change directions ofand to start and stop the movement of materials in a forming operationwherein the forming operation is carried out at high speeds.

In view of the foregoing, it is an object of the inven- .tion to providea novel set of rolls wherein a can body blank or a similar blank may bemoved longitudinally through the rolls ina continuous operation and thematerial of the body blank is so stressed that as it exits from therolls, it begins to assume a generally cylindrical shape with the axisthereof disposed in the general direction of movement.

Another object of the invention is to provide a novel set of rollsthrough which a blank may be passed in a longitudinal direction, andwhich rolls are so configurated to result in the plastic deformation ofareas of the blank in the manner that as the blank exits from the set ofrolls, the plastic deformation of the areas of the blank Will result inthe blank assuming a generally cylindrical shape having an axisextending longitudinally of the direction of movement of the blankthrough the rolls.

Another object of the invention is to provide a novel method of rollforming sheet material, such as can body blanks, wherein the sheet blankmaterial is passed between two rolls and while within the rolls,alternating areas thereof are subjected to plastic deformationandlelastic deformation so that the stresses within the metal of thefiat blank will result in the blank assuming a circular cross-section asit is progressively released by the rolls.

Another object of the invention is to provide a novel can body or othertype of tubular member which is selfretaining in its tubular shape dueto the existence of areas of plastic deformation.

A further object of the invention is to provide a novel tubular member,such as a can body, wherein the tubular member has been formedfrom aflat sheetblank and the circular cross-section thereof is accomplishedby subjecting areas of the blank to plastic deformation, the areas ofplastic deformation being in the form of two sets eX- tending spirallyabout the tubular member and disposed in crossing relation, the areas ofplastic deformation both effecting the shaping of the metal andfunctioning as a decoration thereto. 7 p

Still another object of the invention i to provide a novel method offorming can bodies wherein a can body blank is first passed between apair of rolls and areas thereof are subjected to plastic deformation sothat as the blank passes through the rolls, the blank will be shapedthrough the formation of the plastic deformed areas into a partialcircular cross-section with theaxis thereof exblank through the, rolls.

Patented June 8, 1965 the can .body will have a true circularcross-section.

With the above, and other objects in view that will hereinafter appear,the nature of the invention will be more clearly understood by referenceto the following de tailed description, the appended claims, and theseveral views illustrated in the accompanying drawings:

In the drawings: l

FIGURE 1 is a schematic perspective view showing a flat sheet blankpassing between rolls of a set of rolls formed in accordance with theinvention, withthe blank having areas thereof deformed, alternating onesof the areas being subjected to plastic deformation and the others beingsubjected to elastic deformation wherein as the sheet material passesout from between the rolls, it assumes a' generally cylindrical shape.

FIGURE 2 is an enlarged fragmentary vertical seetional view takenthrough the mating portions only of the rolls, and shows the specificconfiguration thereof, and the shaping of the sheet material whilewithin the rolls, intermediate portions of the rolls and sheet materialbeing omitted.

FIGURE 3 is a perspective view of a cemented can body formed inaccordance with the invention.

FIGURE 4 is a transverse sectional view taken through ;-the can body ofFIGURE 3 and shows the cross-section thereof, r 1

FIGURE 5 is an enlarged transverse sectional view showing-a modifiedshaping of the blank wherein the tubular cross-section is-incomplete.

FIGURE 6 is an enlarged view similar to FIGURE 5, and shows a form ofshaping wherein the edges of the blank abut one another in the formingof a complete circle.

FIGURE 7 is an enlarged perspective view of a modified form ofcan bodysimilar to that of FIGURE 3, but

wherein the areas of plastic deformation are arranged in two setsextending spirally about the can body in crossing relation, and theareas of plastic deformation defining an ornamental pattern to enhancethe appearance of the can body. V

FIGURE 8 is a fragmentary developed view of a roll which may be used inthe forming of the can body of FIGURE 7.

It is well known to pass a flat blank through a pair of rolls to effecta curving of the flat blank and with the longitudinal axis of theresultant curved article being disposed at right angles to the directionof movement of the However, when this arrangement is used in a can bodymaker, for example, it isnec- .essary that the blank be stopped andstarted twice, and -that ,it changes direction ofmo-vement degreestwice.

This,i of course, is undesirable in that it is highly desirable toeliminate all stopping and starting of movement of can body blanks tothus eliminatereciprocating forces and increase the speed of movement ofthe blank through the can body maker; It is to this end that the presentcular shape having an aXis disposed longitudinally .of the I directionof movementof the blank.

Reference is made to FIGURE 1, wherein a conventional can body blank Bor a similar blank is illustrated. The blank is provided in a flat stateand is normally 9 formed of sheet metal. The blank B is passed between a1 pair of rolls 10 and 1 1, and asit passes between the rolls structure.

10, 11, the material of the blank B is stressed in a manner to effectthe movement of the material of the blank into a generally cylindricalshape as it exits from between the rolls and 1 1. It is-t-o beunderstood thatv the configurations of the rolls 10, 1.1 are onlyschematically illustratecl in 'FIGURE -l, and the true section of eachrolling surface of the two rolls is best illustrated in FIG- URE/2. I

The roll 11 is formed of a nonyielding material and 'is very rigid, Theroll 1-1 is provided with annular ribs 12 which are disposedat spacedintervals along the length of the roll 11. Each rib 12 is relativelynarrow and has generally semi-circular cross-section. Thus, each rib 12presents an arcuate sheet engaging surface. The roll 11 is substantiallyflatbetween adjacent ones of the ribs 12.

The roll 10, which roll is disposed uppermost, has a surface defined bya plurality of closely spaced, relatively wide ribs 13. V The ribs..13are also of a partially circular cross-section so as to present anarcuate sheet engaging surface; The radius of curvature'of each of theribs 13 is much greater than that of each of the ribs 12, It

is to be noted that the intersection between adjacent ribs 13 definesgenerally recessed V-areas 14. i

The ribs 12 and Bare disposed in opposed staggered relation. The ribs 12generally seat within the V-areas 14,.and the ribs 13 generally seat inthe flattened areas between the ribs 12. i

As the blank B passes between the rolls 10, 11, the

"material thereof 'is shaped over the ribs 12 and 13;; The

ribs12 being relatively sharp as compared to the ribs 13,

as the blank B is shaped over the ribs 12, there is set up in the blankB localized areas having plastic deformation. On the other hand, thecurvature of the ribs 13 is relatively fiat, with the result that theportions-0f the blank B shaped over the ribs 16 are subject only toelastic deformation. It is to be understood that the deformations of theblank B are greatly exaggerated in FIGURE 2,

and that actually the numerous deformations are so minute that in mostinstances, even the areas of formation are not readily ascertainable.

As the metal of the blank B passes from between the 7 rolls 10, 11,it'progressively stress relieves itself and forms into a cylindricalshape. Thefinal shape of the originalblank B maybe cylindrical havingabutting of the edges of the original blank, cylindrical with overlappededges, or that of only a partial cylinder, the edges of the blank beingspaced apart. These three alternatives are illustratedin FIGURES 6, 4and 5, respectively;

The shaping of the blank B by passing it between the rolls 1t), 11 mayfunction equally as well-in a can body having a hooked and lapped seam,one having a lapped seam, or one having a welded seam. In the case ofthe lapped seam, the lapped edge portions of the original plastic de- 7for bumping, in the case of a can body having a lapped and locked seam,cementing inthe case of a lapped seam, and welding in the case of eithera lapped or butt seam. When the blank B initially assumes its tubularshape, it has visual surface irregularities along the lines of plasticdeformation. However, the stressing of the partially formed blank .ofFIGURE 5 in a'conventional can body maker will result in thedisappearance of the visual surface irregularities, and the .canbody'will have a true circular cross-section.

Inthe blank shaping operation herein described, the i ribs 12,13 extendannularly about the rolls 10, 11, respectively, with the result thatthe-areas of plastic deformation and elastic deformation extendlongitudinally of the can body. However, it is not necessary that theareas of deformation extend longitudinally of the can body. If desired,the areas of deformation may extend spirally about the can body, and itis preferred that two sets of spirals be disposed in crossing relation,as is best illustrated in FIGURE 7. Such an arrangement provides a canbody which is not subject'to' paneling, as is the case of the can bodyformed with the rolls 1%, 11.

Further, the particular spiral crossing arrangement of the areas ofplastic deformation provides a highly ornamental design on the exteriorsurface of the can body so as to enhance the appearance of the can body.The

numerous lines on the surface of the can body 17 indicate can body inFIGURE 7 is referred to, by the numeral 18 and is shown as having alapped seam 19. However, the seam could be butt or lapped and locked, ifdesired. The

' lines or areas of plastic deformations, the lines being referred to bythe numeral 20. I

In. FIGURE 8, there is illustrated a fragmentary developed view of aroll which corresponds to the roll 11,

but is specifically designed for effecting the deformation of thematerial from which the-can body 18 is formed.

This latter roll is referred to in general by the numeral 21 and differsfrom the roll 11' in that it is provided with two sets of ribs 22 whichare'spirally arranged and which are disposed in crossing relations. Theroll '21 may be used in conjunctionwith either another rigid' rollcorresponding to the roll 10, butconfigurated to match the roll blankmay be secured together either by cementing or Welding, as desired. Atypical lapped seam can body is illustrated in FIGURE 3 and is referredto by C. The "details of the lapped edges are clearly shown in thesectional view of FIGURE 4. The can body C may be shaped entirely by theuse of therolls 10,11, with the shape being maintained only during thecementing operation by a suitable holding means in a conventionalmanner, or the shaping and cementing of the can body C may be atleastpartially accomplished in a conventionallcan body maker. i

Reference is now made to FIGURE 6 wherein a sectional viewtaken througha modified. formofcan body C isillustrated. The edges of the'sheetmaterial are,

abutted together as at 15 and may be secured togetherby a weldingoperation or by other securing. means.- The abutting together of theedges of the sheet material may either be accomplished byprimarilyutilizingthe set of rolls 1t 11 and suitable guide means, or byutilizing the set ofrolls together with a conventional canbody maker 21,or it may be used in conjunction with a resilient roll,

such as one having a hard rubber facing layer. Further,

it is to be understood that the roll 11 could be used with a plain rollhaving a hard rubber facing layer in lieu of the roll 10. However, theroll 10 assists in the deforming of the material of the blank B.-

From the foregoing, it will be seen that novel and advantageousprovision has been made for carrying out the desired end. However,attention is again directed to the fact that variations may be made inthe example ,rnethod and apparatus disclosed herein without departingfrom the spirit and scope of theinvention, as defined in i the appendedclaims.

We claim:

1. A method of shaping a fiat sheet blank into a tubular shapecomprising the steps of longitudinally feeding. the blank, progressivelysubjecting spaced areas of the'blank while inaflat state to formingforces normal to the direction of feedto plastically deform the blankand effective to cause the blank to tend toassume a generally circularcross section with the axis thereof normal to the forming forces andparallel to the directionof feed, and

. releasing the stressed portion of the blank to permit the In FIGURE 5,the blankB has been any partially shaped and. the cross-section thereofis a partial circle,

,blank to assume a generally circular cross section.

2. A method of rolling a flat sheet blank into a tubular.

shape comprising the steps 'o-f longitudinally feeding the blank.between opposed .rolls, progressively subjecting spaced areas of theblank while in a flat state to plastic deformation within the rollseffective to cause the blank to tend to assume a generally circularcross section with the axis thereof normal to the axes of the opposedrolls, and releasing the stressed portion of the blank to permit theblank to assumea generally circular cross section.

3. A method of shaping a fiat sheet blank into a tubular shapecomprising the steps of longitudinally feeding the blank, progressivelysubjecting spaced diagonally extending and crossed areas of the blankwhile in a fiat state to forming forces normal to the direction of feedto plastically deform the blank and effective to cause the blank to tendto assume a generally circular cross section with the axis thereofnormal to the forming forces and parallel to the direction of feed, andreleasing the stressed portion of the blank to permit the blank toassume a generally circular cross section.

4. A method of rolling a flat sheet blank into a tubular shapecomprising the steps of longitudinally feeding I the blank betweenopposed rolls, progressively subjecting spaced diagonally extending, andcrossed areas of the blank while in a flat state to plastic deformationwithin the rolls efiective to cause the blank to tend to assume agenerally circular cross section with the axis thereof normal to theaxes of the opposed rolls, and releasing the stressed portion of theblank to permit the blank to assume a generally circular cross section.

5. A method of rolling a flat sheet blank into a tubular shapecomprising the steps of longitudinally feeding the blank between opposedrolls, progressively subjecting longitudinally extending alternatingareas of the blank while in a flat state to plastic deformationeffective to cause the blank to tend to assume a generally circularcross section with the axis thereof normal to the axes of the opposedrolls, and releasing the stressed portion of the blank to permit thestressed portion to stress relieve itself and assume a generallycircular cross section.

6. A method of forming a can body from a fiat sheet blank comprising thesteps of longitudinally feeding the blank between opposed rolls,progressively subjecting spaced areas of the blank to plasticdeformation within the rolls effective to cause the blank to tend toassume a generally circular cross section, releasing the stressedpertion of the blank to permit the blank to assume an open.

partially circular cross section, and then stressing the blank to itsfinished circular form through a conventional can body making operationin a conventional can body maker thereby eliminating visual evidence ofthe areas of plastic deformation.

7. A cylinder-forming roll assembly comprising a set of opposing rolls,a path normal to and from the axis of each roll of the set of opposingrolls whereby a flat sheet blank may be'transported to, between and fromthe rolls along said path, one roll of said set of opposing rolls beingprovided with first means cooperative with complementary second means onanother roll of said set of rolls, said first means and saidcomplementary second means being constructed and arranged toprogressively plastically deform-a flat sheet blank along linearlyextending areas thereof for curling lateral edges of the blank towardeach other about an axis parallel to said path whereby said fiat sheetblank is formed into a cylinder along the path extending from and normalto the axes of said rolls, said first means comprising a plurality ofwidely spaced projecting narrow ribs for plastically deforming the flatsheet blank from one side, and the complementary second means comprisinga plurality of closely spaced wide ribs in staggered mating relationwith said narrow ribs.

8. The cylinder-forming roll assembly of claim 7 wherein said narrowribs and said wide ribs having arcuate sheet engaging surfaces.

References Cited by the Examiner UNITED STATES PATENTS 2,006,827 7/35Feller 220-83 2,075,286 3/37 Jackes.

2,277,725 3/42 Smith et al. 153-77 2,352,675 7/44 Yoder 153-28 2,391,76612/45 Barnhart 29-534 2,438,844 3/48 Pale 220-83 2,471,490 5/49 Mercer153-28 2,702,429 2/55 Peters et a1 29-534 2,986,193 5/61 Howell 155-77CHARLES W. LANHAM, Primary Examiner.

NEDWIN BERGER, Examiner.

1. A METHOD OF SHAPING A FLAT SHEET BLANK INTO A TUBULAR SHAPECOMPRISING THE STEPS OF LONGITUDINALLY FEEDING THE BLANK, PROGRESSIVELYSUBJECTING SPACED AREAS OF THE BLANK WHILE IN A FLAT STATE TO FORMINGFORCES NORMAL TO THE DIRECTION OF FEED TO PLASTICALLY DEFORM THE BLANKAND EFFECTIVE TO CAUSE THE BLANK TO TEND TO ASSUME A GENERALLY CIRCULARCROSS SECTION WITH THE AXIS THEREOF NORMAL TO THE FORMING FORCES ANDPARALLEL TO THE DIRECTION OF FEED, AND RELEASING THE STRESSED PORTION OFTHE BLANK TO PERMIT THE BLANK TO ASSUME A GENERALLY CIRCULAR CROSSSECTION.